The effect of temperature and milling process on steel scale utilized as a pigment for ceramic glaze

This study is focused on the evaluation of the re-utilizability of scale originated during the steel casting and steel rolling processes as a pigment for glazes. Non-oiled scale with Fe3O4 as the major phase were used as a coloring component of transparent glaze matrix in: (i) as received state, (ii) thermally pre-treated at 700 and 900 degrees C, (iii) mechanically treated in planetary ball mill (60, 120 and 240 min) and (iv) mechanically treated in vibratory disc mill (60 and 120 min). Prepared glazes were applied on the surface of ceramic tiles prepared from a commercially available white ceramic slurry. The resulting tiles with given glaze were thermally treated at 800, 900 and 1060 degrees C. The pigments were characterized by X-ray powder diffraction method (XRD), X-ray fluorescence spectroscopy (XRF), granulometry (PSD), thermogravimetric analysis (TG) and differential thermal analysis (DTA), scanning electron microscopy (SEM/EDAX). The color of the samples was described by the coordinates L*a*b* from CIELAB color space. The results showed that the non-oiled scale is suitable as the pigment for ceramic glazes. Careful control of the scale treatment process (mechanical as well as thermal) together with the temperature of final glaze firing is necessary to obtain the glaze of desired color and quality.Web of Science138art. no. 181

The administration of Přerov in the historical development

V roce 2003 proběhla II. fáze reformy veřejné správy, okresní úřady zanikly. Proto je cílem této práce najít odpověď na otázku, zda fungoval současný systém veřejné správy i v minulosti. Vývoj správy popisuji od doby vzniku měst do současnosti, zaměřuji se na město Přerov.Ústav veřejné správy a právaDokončená práce s úspěšnou obhajobo

Evolution of the Bohemian Massif: Insights from numerical modeling

The Bohemian Massif was consolidated during the Variscan orogeny (~400-300 Ma), which involved several oceanic subductions and collisions of continental micro-plates. The central part of the Bohemian Massif, the Moldanubian domain, shows a large accumulation of felsic high-pressure metamorphs. We present a numerical model of exhumation of these rocks due to continental collision and underthrusting. The key feature of the model is a felsic (light, rheologically weak and rich in radioactive elements) material in the lower crust of one of the colliding blocks. We examine the influence of the rate of convergence of the two blocks, radiogenic heating in the felsic lower crust and efficiency of erosion, on the model evolution and pressure-temperature conditions in the lower-crustal material. The models where the material is sufficiently weakened due to radiogenic heating show formation of an orogenic plateau, sedimentation in a foreland basin, and crustal thickening accompanied by gravity-driven exhumation of the lower crust and subsequent sub-horizontal flow in the middle crust. In colder and/or faster models, the thickening is dominated by folding. We correlate the tectonic style of these two types of models with differences between the high-grade rocks in the southern (Moldanubian) and northern (Sudetic) parts..

The role of tidal heating in the dynamics of icy satellites

Katedra geofyzikyDepartment of GeophysicsMatematicko-fyzikální fakultaFaculty of Mathematics and Physic

The measurement and the classification of the effectiveness of the health care

Cílem této práce je poukázat na možné metody hodnocení efektivnosti zdravotní péče a odpovědět na otázku, zda je vhodné hodnotit činnost zdravotnických zařízení nejen pomocí finančně-ekonomických ukazatelů, ale i ve vzájemné spojitosti s výkonnostními ukazateli.The objective of this work is it refer to the possible methods of the classification of the effectiveness of the health care and answer to the question, whether it is acceptable to value the performance of the medical establishements not only by means of the economic indicators, but in the dependence with the efficiency indicators.Ústav ekonomiky a managementuDokončená práce s úspěšnou obhajobo

Fyzikální model vývoje Českého masivu

Český masiv byl konsolidován v důsledku kolize několika kontinentálních mikrodesek v průběhu Variského vrásnění (~400-300 Ma). Centrální část Českého masivu, Moldanubikum, obsahuje významné množství felsických vysoce metamorfovaných hornin. V této práci představujeme numerický model kontinentální kolize, která vedla k výstupu těchto hornin. Důležitým předpokladem modelu je felsické složení spodní kůry jednoho z kolidujících kontinentálních bloků, a z toho vyplývající její nízká hustota a viskozita a vysoký obsah radioaktivních prvků způsobujících zahřívání materiálu. Zkoumali jsme vliv koncentrace tepelných zdrojů, rychlosti kolize a povrchové eroze na deformaci kůry a na tlakově-teplotní podmínky ve spodněkorovém materiálu. Při časovém vývoji dochází v modelu ke ztluštění kůry, růstu náhorní plošiny a sedimentaci v předpolní pánvi. Pokud je spodní kůra dostatečně změkčená v důsledku radioaktivního zahřívání, je ztluštění kůry doprovázeno gravitačně indukovaným výstupem spodněkorových hornin a následně subhorizontálním tečením ve střední kůře. Naproti tomu v chladnějších a rychlejších modelech je hlavním mechanismem ztluštění kůry vrásnění. Tyto dva typy chování vystihují pozorované rozdíly mezi felsickými vysoce metamorfovanými horninami v moldanubické a v sudetské části Českého masivu.The Bohemian Massif was consolidated during the Variscan orogeny (~400-300 Ma), which involved several oceanic subductions and collisions of continental micro-plates. The central part of the Bohemian Massif, the Moldanubian domain, shows a large accumulation of felsic high-pressure metamorphs. We present a numerical model of exhumation of these rocks due to continental collision and underthrusting. The key feature of the model is a felsic (light, rheologically weak and rich in radioactive elements) material in the lower crust of one of the colliding blocks. We examine the influence of the rate of convergence of the two blocks, radiogenic heating in the felsic lower crust and efficiency of erosion, on the model evolution and pressure-temperature conditions in the lower-crustal material. The models where the material is sufficiently weakened due to radiogenic heating show formation of an orogenic plateau, sedimentation in a foreland basin, and crustal thickening accompanied by gravity-driven exhumation of the lower crust and subsequent sub-horizontal flow in the middle crust. In colder and/or faster models, the thickening is dominated by folding. We correlate the tectonic style of these two types of models with differences between the high-grade rocks in the southern (Moldanubian) and northern (Sudetic) parts...Katedra geofyzikyDepartment of GeophysicsMatematicko-fyzikální fakultaFaculty of Mathematics and Physic

Estimating the rheology parameters of icy satellites from observed surface deformations

Katedra geofyzikyDepartment of GeophysicsFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult

Estimating the rheology parameters of icy satellites from observed surface deformations

Katedra geofyzikyDepartment of GeophysicsFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult

Quantitative evaluation of crystalline and amorphous phases in clay-based cordierite ceramic

An innovative chemical quantitative mineral analysis (CQMA) was successfully tested on a cordierite-based clay ceramic sample to quantify crystalline and amorphous components. The accuracy of this method was demonstrated on an added module to the CQMA program that used oxide formulas of amorphous phases obtained by energy dispersive X-ray spectroscopy (EDS) microprobe chemical analysis. This CQMA method was tested for three variants calculated using chemical analysis, i.e., X-ray diffraction (XRD) identification of crystalline (cordierite and enstatite) and amorphous phases by scanning electron microscopy (SEM)/EDS texture and microanalyses. The test results from CQMA suggest their application possibilities as well as the limits of their utilization.Web of Science1012art. no. 112

Effect of mass ratio and milling on compressive strength and corrosion resistance of blast-furnace slag/fly ash geopolymer activated by solid alkali activator

Fly ash and granulated blast-furnace slag can be considered "multifunctional waste." This study is focused on properties of a non-cement binder prepared from slag and fly ash activated by solid alkali activator. Fly ash was milled (2.5, 5.0, and 7.5 min) in order to increase its reactivity, and particle size distribution, specific surface area, and grain morphology were determined for all milled FA samples. Two GBFS +FA mixtures (70:30 and 85:15 w/w) were studied. Prepared mixtures were activated by solid alkali activator (Na2SiO3). Optimal weight ratios were calculated for CaO, SiO2, and Al2O3 components. Properties of the mixtures were studied in dependence on the GBFS:FA mass ratio and FA milling time (0-7.5 min). After 2 and 28 days of hydration, compressive strength of all mixtures exceeded 20 and 60 MPa, respectively. The 85:15 ratio led to generally higher compressive strength 108.3 MPa was reached after 90 days using FA milled for 7.5 min. Corrosion resistance was tested by exposing mixtures to distilled water, 0.5% HCl, and 3% Na2SO4 for 65 days, and evaluated by measuring changes in CS. Also the corrosion resistance was found higher (Na2SO4) than and comparable (HCl, water) to the 70:30 ratio. This study aims to show that GBFS +FA mixtures (70:30 and 85:15 w/w) activated by solid Na2SiO3 can achieve high CS and good corrosion resistance.Web of Science841974196